Two studies of the motion of ions within an ion cyclotron resonance spectrometer have been completed and mathematically modeled with computer simulations. Ion transfer between cells in a dual cell spectrometer has been found to occur on a more harmonic potential surface than expected. These results suggest that only ions formed near the center of the source cell can be effectively transferred and/or detected. Further, the transfer of ions can be disrupted in a cyclic manner by magnetron motion. The oscillations observed in transfer efficiency are consistent with a simple geometric model in which ion motion about the equipotentials in the x-y plane of the cell is slightly displaced relative to the conductance limit hole. Additional refinement of continuous flow liquid second ion mass spectrometry for quantitative analysis of polar organic compounds has been developed at the subnanogram level for compounds of importance to neurotoxicological studies. A new p cesium ion gun has been developed and tested with spot sizes of 2-3 mm and 0. 1-0.2 mm. Significantly improved mass spectrometric performance was realized with this device which is suitable for routine operation.